demand

# demand

1. ### Maximum demand exceeding main fuse.

I've got a customer who currently has a 60A main fuse running in 10mm tails to a board with breakers 32/32/20/6/6A which, doing the diversity calc at biggest breaker + 40% of the rest comes in at 57.6A, just about OK. She wants a new 32A cooker circuit, so I said she should get the tails...
2. ### How are you calculating maximum demand

How are you calculating maximum demand for the certificate and what should you do if your calculations exceed the main fuse rating?
3. ### SSE on-line demand calculator

Just for general info, I happened across this on-line tool this morning: https://www.ssen.co.uk/our-services/tools-and-maps/demand-calculator/ Seems a handy way to estimate a property's peak demand and what the DNO might have assumed for overall network demand after diversity.
4. ### Calculation question.

Hello, I have a question about diversity and load utilisation factor with Trimble software. Say we have a 3ph 150kW load with 0.8 pf which gives 187.5 kVA and we also have a diversity of 0.8 and a load utilisation factor of 0.9. Applying these factors we will end up with a kVA of 135kVA...
5. ### Commercial Max Demand Course?

I've seen some companies doing max demand calculations/reports on commercial properties and this would be useful for us to do. However we don't have anyone who is skilled/knows enough to do this. Although our team is very experienced this seems like a niche we don't have experience in. However I...
6. ### Maximum demand and diversity

Hey guys I really need urgent help understanding this Basically I'm trying to calculate what the diversity factor/percentages would be for the following circuits which are inside a hotel: 3x 32A socket outlet circuit 2x Vending machine circuit Fridge circuit Dishwasher Servery food holding...
7. ### Maximum demand and EVCP's

I'm always in a dilemma with regards max demand. Often you work it out and it's higher than the the 80A or 60A cut out fuse. However, you know that in reality it is absolutely fine. I have thought about this in the past when installing electric showers. Now with EVCP's as well it's making me...
8. ### Kva 3phase demand calc

Hello all, looking for a bit of advice not been asked to fill in a new power supply for dno for a commercial premesis before. Do i put 70kva for a 3 phase supply that equates to 100A 3 phase head? Usually on single phase i put 18.4kva for 80 supply and they always provide 100A head. Thanks in...
9. ### Max demand fun

This isn't sitting right with me. So if I rock up at a house with a 60A suppliers fuse, it has a dear old Wylex with 1 RFC 30A (no diversity) 1 Cooker 30A (no data to hand, plate has socket, assuming 21.6A for now) 1 Shower 30A (7.5Kw - full rating) 2 Lighting 5A ( 21 points total * 100w * 0.6...
10. ### Fluke 43b help and logging max demand

Hi all, I have brought a fluke 43b to log a local farm to see how many amps they are using at maximum demand. The meter gives 3 readings for each time interval. Min, max and average. I would understand if the readings were between 2 time periods, but don’t understand how you can have three...
11. ### Vacuum on Demand (vid) supply on farm

Hi, thanks for any advice. I have been asked to install supply for vod for vac pumps on a farm. I have been told it needs own dedicated supply as will trip RCD’s. Could anybody explain why it will trip an RCD ( does it create that much earth leakage?) The local board I was going to feed from...
12. ### Annex supply, (wont give meter) , demand problems

HI all, Ill keep this as short as possible, basically annex off existing Large house, didn't do demand as existing house as swimming pool and its a large 60'shouse told customer either upgrade existing house to 3 phase or new supply to Annex Annex . Electric UFH thoughout (1 bed annex with...
13. ### UK Outbuilding Supply from house maximum demand

A couple of questions for you. The electrician that rewired our house ran a 10mm2 SWA to our outbuilding. The total length of the cable is about 45m. It is in ducting underground at a depth of approximately 1.2m. Now, my understanding is that the max load for 10mm2 underground over 45m would...
14. ### Max demand for double oven and hob

Just some clarification please. Max demand for cooking devices. OSG says 10A + 30% of "connected cooking appliances in excess of 10A + 5A" if a socket is available in the isolator. The oven and hob are two devices. Does the 15A apply to both of them or just the first one? eg: Oven 4.8 kW Hob...
15. ### Peak demand load controller

Does anyone know of a controller that can turn off loads as the demand goes up? I have a house with 10x2.7kw heaters installed, the obvious problem is if there all on that's 27kw on a 100amp single phase property, there's no option to go to 3 phase and no capacity for any other appliances to...
16. ### UK Maximum demand

Hi All I am doing my assignment and one of the tasks is to create a fuse board schedule showing circuit breaker ratings any assumptions must be stated with reasoning given. using these circuits calculate the maximum demand of the installation Can someone tell me if it is right So without...
17. ### Door shutter rcd!

Hello I have an oportunity to take one big commercial job! there would be 4 -3 phase door shutter!i think 16 amps socket! should i put rcd on each shutter or one enought for 4 shutter? should i protect the ciruitS by rcd? the cable will run on very high level on the cable tray ! if yes ,where...
18. ### What physical jobs does the NVQ3 demand?

I've asked several colleges and training providers now 'what is needed to complete the NVQ3' and nobody will actually give me an answer. I keep getting 'portfolio showing comptence'. So....anyone who has done it - what actual jobs are needed to be able to pass the NVQ3? Are there any in there...
19. ### Max demand & diversity advice needed

I have been asked to do some work on a large 25 room mini mansion spread over 3 old properties made in to 1 with 6 consumer units on a single phase 100amp supply. The total loading of the breakers is 452 amps if I apply diversity at 40% I arrive at 180.8amps demand but this dose not take in to...
20. ### Maximum demand calcs

Hi guys. Just looking at how people work out their max demand for supplies to consumer units. Looking at a board change with 7 circuits and going by osg working out to be over 80a I have heard of the 40% rule of total load but was wondering if any others have a different method. I cant see an...